Journal of Integer Sequences, Vol. 25 (2022), Article 22.9.1

Extreme Covering Systems


Jack Dalton and Ognian Trifonov
University of South Carolina
Department of Mathematics
Columbia, SC 29208
USA

Abstract:

We prove that if the least modulus of a distinct covering system is 4, its largest modulus is at least 60; also, if the least modulus is 3, the least common multiple of the moduli is at least 120; finally, if the least modulus is 4, the least common multiple of the moduli is at least 360. The constants 60, 120, and 360 are best possible---they cannot be replaced by larger constants.


Full version:  pdf,    dvi,    ps,    latex    


Received March 18 2022; revised versions received March 24 2022; August 18 2022. Published in Journal of Integer Sequences, October 27 2022.


Return to Journal of Integer Sequences home page